Fognini sparked widespread controversy after using the offensive Italian word repeatedly during the three-set loss to Russian player Daniil Medvedev in the third round on Wednesday.
Fognini took to Instagram early Thursday to apologise, writing that the scorching heat “affected his head” and caused him to “use a really stupid expression toward myself”.
“Obviously I didn’t want to offend anyone’s feelings,” Fognini added.
“I love the LGBT community and I apologise for the nonsense that I let out.”
Throughout the match, Fognini could also be seen repeatedly smashing his racket, before throwing it out after the final point.
Both players struggled in the heat, with Medvedev nearly fainting during the match.
Asked by the umpire if he was OK during the second set, the Russian replied: “I can finish the match, but I can die. If I die, who will take responsibility?”
The hot-tempered Fognini has been reprimanded in the past for using offensive language.
He was disqualified in Barcelona in April for having offended a line umpire.
In 2017, he was kicked out of the doubles tournament at the US Open for using directing misogynistic language at the chair umpire during his first-round loss in singles.
He was then handed a suspended ban of two Grand Slam tournaments.
At Wimbledon in 2019, he received a £10,000 fine for saying “I wish a bomb would explode on this club”, during a match against American Tennys Sandgren.
